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This shell is very likely a remain of a relictual population, now probably extinct, of the French Atlantic coast.
I could only find reference to that population in french : https://doris.ffessm.fr/Especes/Cerithium-vulgatum-Cerithe-goumier-1177

Here is a translation of the interesting part : " It appears that this species [Cerithium vulgatum] lived until recent times on the Atlantic coast [of France]; some rolled or broken shells were found on the beaches of La Baule and its surroundings."